function $(id){
  return document.getElementById(id);
}

function createXMLHTTP(){
  var xmlHttp=null;
  try{
    xmlHttp=new XMLHttpRequest();   } 
  catch (MSIEx){
    try{
      xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");     }
    catch (e){
      try{
        xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");       }
      catch(e){alert('您的浏览器不支持AJAX！');}
    }
  }
  return xmlHttp;
}

function chk(){
  var username=$('username').value;
  var password=$('password').value;
  
  if (username==""){
    alert("请填写用户名！");  $('username').focus(); return false;
  }
  else if (password==""){
    alert("请填写密码！");  $('password').focus(); return false;
  }

    var html
    html="<!--登录状态显示.start-->"
    html+="<!--登录状态显示.end-->"
   $('msg').innerHTML=html;
  
  //AJAX无刷新注册
  var url="login.asp?username="+username+"&password="+password+"&t="+new Date().getTime();//每个时间的缓存解决
  var x=createXMLHTTP();
  x.open('GET',url,true)
  x.onreadystatechange=function(){callback(x);} 
  x.send(null)
}

function callback(x){
  if (x.readyState==4){
    if(x.status==200||x.status==0){
      var s=x.responseText;
      if(s.length>0&&s=="YES"){
        $('login').style.display="none";//隐藏注册DIV     
        $('msg').style.display="block";//显示信息DIV
      }
      else{
        alert("您的帐号不存在或密码输入错误,请重新输入!!")
      }
    }
  }
}

if session("xxx")="" then
  response.write "0"
else 
 response.write "1"
end if